The purpose of this longitudinal study is to evaluate a developmentally-oriented bio-neuropsychosocial model of psychological adjustment in young adolescents with spina bifida (10-13 years old at Time 1 and 12-15 years old at Time 2). Extensive multi-source and multi-method data will be collected across several predictor variable domains: (1) biological, (2) neuropsychological, and (3) social. A multidimensional perspective on adolescent adjustment will also be adopted, with a rigorous focus on the adolescents'social adjustment. The proposed study will be the first to collect observed peer, interaction data (target child with close friend) in adolescents with spina bifida. The degree to which neuropsychological limitations experienced by children with spina bifida contribute to their social difficulties and other psychological problems will also be examined. Participants will include a sample of 140 children and young adolescents with spina bifida (with meningomyelocele and shunted hydrocephalus) along with their parents, a close friend, teachers, and health professionals. Spanish-speaking Hispanic/Latino families will also be recruited. Questionnaire, interview, neuropsychological testing, and observational methods will be employed during two home visits at Time 1 and two home visits at Time 2. In addition to evaluating the utility of the bioneuropsychosocial model, several mediational and moderational models will also be tested within the context of the more general model. Such models will facilitate identification of underlying mechanisms for associations between variables (i.e., mediational models) and will attempt to isolate variables within one domain that compensate for deficits in another domain (i.e., moderational models). Findings of this study will provide information on the differential relevance of family relationships, peer relationships, neuropsychological factors, and biological factors for adjustment in adolescents with spina bifida. Moreover, the results will have implications for prevention and intervention efforts with families who have offspring with disabling birth defects.